Peristaltic pump including an elastically displaceable locking plate

ABSTRACT

A peristaltic pump is provided. The peristaltic pump includes a housing for a motors a receiving plate mounted to the housing, a locking plate, and a biasing member. The locking plate includes a first aperture capable of receiving a hook extending from a pump head, a second aperture capable of receiving a drive shaft of the pump head, and a release member. The biasing member elastically couples the receiving plate with the locking plate. Use of the release member by a user causes movement of the locking plate relative to the receiving plate to release the hook when received in the first aperture thereby releasing the pump head from the locking plate.

FIELD

The field of the disclosure relates generally to peristaltic pumps. More specifically, the disclosure relates to a peristaltic pump head that can be mounted to the peristaltic pump using an elastically displaceable locking plate.

BACKGROUND

Peristaltic pumps have been known for many years, and are commonly used for medical and research purposes. Peristaltic pumps are used, in particular, in research, environmental science, and chemistry laboratories, and in the pharmaceutical, biotechnology, agriculture, and food industries. Peristaltic pumps move a liquid through a tube without any part of the pump touching the liquid. As a result, it is possible to pump liquids, such as blood, which are sensitive to external contamination.

Typically, a pump comprises rotating rollers that compress a part of the flexible tube as they move to propel the liquid through the tube. Some peristaltic pumps have at least one removable head through which passes the tube in which the fluid flows. The rollers mount on the periphery of a central hub of the head and are driven to rotate thereby compressing the tube in succession against a fixed wall. The alternation of pressure and release phases of an area of the tube pumps the fluid to be delivered.

Some peristaltic pumps include a plurality of heads which can be mounted adjacent to each other and driven to rotate by the same actuator. As a result, the first head of the stack can be fixed on a module having a motor connected to means for driving the central hub of the head. Any remaining heads can be fastened in succession, starling at the front face of the first head. Each head is also connected to the means for driving the central hub of the preceding head. Inclusion of a plurality of heads enables the supply of a fluid using a single drive module. This is particularly useful, for example, in animal testing laboratories, so that a plurality of animals can receive the same dose of the same liquid at the same time. Peristaltic pumps with stackable heads are described, for example, in EP-A-0 61 9 859 and EP-A-0 339 857. What is needed, however, is a peristaltic pump with stackable heads in which the heads can be very easily added to and/or removed from the pump, particularly without interrupting the operation of the pump for such addition or removal.

SUMMARY

A peristaltic pump including a mechanism for adding and/or removing one or more pump heads to/from the peristaltic pump is provided in an exemplary embodiment. The peristaltic pump includes, but is not limited to, a housing for a motor, a receiving plate mounted to the housing, a locking plate, and a biasing member. The locking plate, includes, but is not limited to, a first aperture capable of receiving a hook extending from a pump head, a second aperture capable of receiving a drive shaft of the pump head, and a release member. The biasing member elastically couples the receiving plate with the locking plate. Use of the release member by a user causes movement of the locking plate relative to the receiving plate to release the hook when received in the first aperture thereby releasing the pump head from the locking plate.

Another exemplary embodiment provides a peristaltic pump. The peristaltic pump includes, but is not limited to, a housing for a motor, a receiving plate mounted to the housing, a locking plate, and a biasing member. The locking plate, includes, but is not limited to, a hook, an aperture capable of receiving a drive shaft of a pump head, and a release member. The biasing member elastically couples the receiving plate with the locking plate. Use of the release member by a user causes movement of the locking plate relative to the receiving plate to release the hook from the pump head when the pump head is mounted to the locking plate.

Other principal features and advantages of the invention will become apparent to those skilled in the art upon review of the following drawings, the detailed description, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention will hereafter be described with reference to the accompanying drawings, wherein like numerals denote like elements.

FIG. 1 is a perspective view of a peristaltic pump including a plurality of pump heads in a position to be installed onto the pump and a pump head mounted to the peristaltic pump in accordance with an exemplary embodiment.

FIG. 2 is a perspective view of a mounting side of a pump head in accordance with an exemplary embodiment.

FIG. 3 is a perspective view of the pump head of FIG. 1 showing detail of the drive shaft of the pump head in accordance with an exemplary embodiment.

FIG. 4 is a perspective view of a receiving plate of the pump drive module of FIG. 1 without a pump head mounted to the drive module in accordance with an exemplary embodiment.

FIG. 5 is a perspective view of the drive module of FIG. 4 showing detail of the drive shaft of the drive module in accordance with an exemplary embodiment.

FIG. 6 is a perspective view of the drive module of FIG. 4 showing detail of the mounting mechanism for mounting a pump head to the drive module in accordance with an exemplary embodiment.

FIG. 7 is a back perspective view of the mounting mechanism of FIG. 4 with a pump head mounted to the drive module in accordance with an exemplary embodiment.

DETAILED DESCRIPTION

With reference to FIG. 1, a peristaltic pump 30 is shown in accordance with an exemplary embodiment. Peristaltic pump 30 may include a drive module 1, a first pump head 32, a second pump head 34, and a third pump head 36. Drive module 1 includes a housing 38 which encloses a motor. The motor drives a central hub of the pump heads 32, 34, 36. Housing 38 includes a control panel 4 and a display screen 5 which enable an operator to adjust operating parameters of peristaltic pump 30. A receiving plate 6 mounts to housing 38. Receiving plate 6 includes an upper face 2 on which a push button 3 is mounted. Using push button 3, the operator can release first pump head 32, or a stack of pump heads connected to drive module 1 as described below. Receiving plate 6 is mounted on drive module 1. As used in this disclosure, the term “mount” includes join, unite, connect, associate, insert, hang, hold, affix, attach, fasten, bind, paste, secure, bolt, screw, rivet, solder, weld, and other like terms.

First pump head 32 includes a cassette 40, a second push button 9, and a second receiving plate 10. Cassette 40 includes an orifice 7 and a slide control 8. Cassette 40 allows a flexible tube (not shown) to be inserted into it in a conventional way through orifice 7. Slide control 8 can be used, also in a conventional way, to adjust the positioning of the internal members of cassette 40 to provide a permanent contact with sufficient pressure between these members and the tube inserted into orifice 7, regardless of the diameter of the tube used. The internal members of cassette 40 are essentially a central hub driven by drive module 1 and its peripheral cylinders which periodically compress the wall of the tube, thus creating the flow of the fluid to be delivered. Cassette 40 is of conventional design, and therefore will not be described or illustrated here. The previously cited prior art documents provide example embodiments of these internal members, whose general design can be included within the scope of the invention in a non-restrictive way. Second push button 9 can be used to unlock the pump heads mounted on second receiving plate 10 of first pump head 32, by means of a mechanism which is described below.

Second pump head 34 is shown ready for mounting on second receiving plate 10 of first pump head 32. In the exemplary embodiment of FIG. 1, second pump head 34 includes four cassettes 40, a mounting plate 11, a third push button 9′, and a third receiving plate 10′. Each of the four cassettes 40 include an orifice 7′. As a result, four flexible tubes, instead of one, can be inserted into second pump head 34. Third push button 9′ can be used to release the pump heads mounted on third receiving plate 10′ of second pump head 34.

Third pump head 36 is shown ready for mounting on third receiving plate 10′ of second pump head 34. In the exemplary embodiment of FIG. 1, third pump head 36 includes two cassettes 40′, a second mounting plate 12, a fourth push button 9″, and a fourth receiving plate 10″ Each of the two cassettes 40′ include an orifice 7″. As a result, two flexible tubes, instead of one, can be inserted into third pump head 36. In the exemplary embodiment of FIG. 1, the two orifices 7″ allow the passage of two flexible tubes of larger diameter than the tubes which can pass through the orifices 7, 7′. As a result, third pump head 36 may be as thick as second pump head 34, which allows the passage of four smaller-diameter tubes. Fourth push button 9″ can be used to release any additional pump heads which may be mounted on fourth receiving plate 10″ of third pump head 36.

With reference to FIG. 2, a perspective view of second pump head 34 is shown in accordance with an exemplary embodiment. A face 13 of mounting plate 11 is shown. Second mounting plate 12 and/or receiving plate 6 may include a similar face 13 for mounting to another pump head. Face 13 includes a plurality of hooks 17 which extend from the surface of face 13 opposite cassettes 40. Face 13 also includes an aperture 42 through which an end of a drive shaft 14 of the central hub of second pump head 34 extends The plurality of hooks 17 allow the operator to fasten second pump head 34 either to a front face 18 of receiving plate 6 or to a mounting plate of another pump head.

With reference to FIG. 3, aperture 42 of face 13 is shown in greater detail. Drive shaft 14 includes splines 15 formed by longitudinal protrusions whose ends have chamfers 16, the function of these being described below.

With reference to FIG. 4, housing 38 with front face 18 of receiving plate 6 visible is shown in accordance with an exemplary embodiment. Receiving plate 6 includes an aperture 44. An end 19 of the shaft driven by the motor of drive module 1 is accessible through aperture 44. A locking plate 22 mounts to receiving plate 6 and includes push button 3. Depression of push button 3 causes displacement elastically and releases a pump head connected to drive module 1. In the exemplary embodiment of FIG. 4, locking plate 22 includes four locking apertures 23 in which the plurality of hooks 17 of the mounting plate engage. With reference to FIG. 6, the entrance of each of the four locking apertures 23 includes a chamfer 24 which facilitates the introduction of the corresponding hook 17.

With reference to FIG. 5, end 19 of the shaft is shown in greater detail. End 19 is shaped in the form of a sleeve whose inner surface has second splines 20 formed by longitudinal protrusions whose ends have chamfers 21. Second splines 20 are designed to receive between them splines 15 of the end of drive shaft 14 of second pump head 34. Drive shaft 14 is mounted to the shaft of drive module 1. The chamfers 15 and 21 facilitate the reception of drive shaft 14 of the head into the sleeve of end 19. As a result, drive shaft 14 can be received into end 19 without the need to stop the motor of drive module 1.

With reference to FIG. 7, a perspective view of locking plate 22 mounted to receiving plate 6 is shown in accordance with an exemplary embodiment. Push button 3 extends from locking plate 22 through an aperture in upper surface 2 of receiving plate 6. Locking plate 22 includes the four locking apertures 23, an aperture 46, and apertures 28. End 19 of the shaft driven by the motor of drive module 1 extends through aperture 46. Locking plate 22 tends to be pushed upwards by biasing members 25, 26, being guided for this purpose by fixed studs 27, which extend from receiving plate 6 and penetrate into apertures 28 of locking plate 22. Biasing members 25, 26 may be springs.

A pump head is mounted to receiving plate 6 by a simple axial movement to engage the plurality of hooks 17 with the chamfers 24 of the four locking apertures 23 of locking plate 22. The plurality of hooks 17 tend to push locking plate 22 downwards to allow passage through the four locking apertures 23. At this point, the springs 25 and 26 push locking plate 22 upwards again locking the plurality of hooks 17 against the four locking apertures 23 of locking plate 22. In the absence of the chamfers 24 or similar chamfers which may be formed on the plurality of hooks 17, it may be necessary to press push button 3 to align the plurality of hooks 17 with the four locking apertures 23. Release of push button 3 locks the plurality of hooks 17 against the four locking apertures 23. At the same time, the end of drive shaft 14 of the pump head penetrates into the end 19 of the shaft of the motor of drive module 1, and the two shafts engage each other. Thus, a rotation of the motor shaft causes a rotation of the drive shaft of the pump head.

A subsequent depression of push button 3 releases the plurality of hooks 17 from the four locking apertures 23. Locking plate 22 is pushed back downwards, thus releasing the plurality of hooks 17 and the pump head from drive module 1 by pulling away from drive module 1.

The receiving plate 10, 10′, 10″ of each pump head 32, 34, 36 is advantageously shaped in the same way as receiving plate 6 and similarly includes a locking plate mounted thereto as described above. in particular, each receiving plate 10, 10′, 10″ includes a locking plate identical to locking plate 22 including the four locking apertures 23 and push buttons 9, 9′, 9″ corresponding to push button 3 of drive module 1. Thus, a plurality of pump heads 34, 36 can be mounted in a sequence starting with first pump head 32. The front end of drive shaft 14 of the central hub of each pump head 32, 34, 36 is shaped in the same way as end 19 of the shaft of the motor of drive module 1, so that the shaft of the central hub of a given pump head 32, 34, 36 receives into itself the shaft of the central hub of the following pump head in the stack to drive the subsequent shaft under control of the motor. Thus, any number of pump heads can be mounted in sequence with the only limitation being the driving power of the motor of drive module 1. Mounting of the pump heads can occur with the motor stopped or with the motor running. This result is achieved, in particular, by the chamfered configuration of the splines 15, 20 of the ends of the shafts, which facilitate engagement, even when there is no exact alignment between the shafts.

If a plurality of additional pump heads 34, 36 are mounted on first pump head 32 connected to drive module 1, push button 3 of drive module I can be depressed to release the whole stack of heads 32, 34, 36 while keeping them connected to each other. it is also possible to unlock a single head 32, 34, 36, or a group of consecutive pump heads, without any need to stop drive module 1. In alternative embodiments, the use of a head which has a mounting plate, but not a receiving plate can be used. in this case, the pump head is the last head of the stack, or the only head connected to drive module 1.

Various modifications are possible. For example, a smaller or a greater number of the hooks 17 and the apertures 23 may be used in a different configuration. Additionally, the direction of displacement of locking plate 22 can be changed, together with the shapes of the hooks 17 and the apertures 23. Push buttons 3, 9, 9′, 9″ can be replaced with any functionally equivalent means enabling the user to displace the locking plates 22. Relative to the method of connecting the shafts 14 of the central hubs of the heads 32, 34, 36 to each other and to the motor shaft driven by the motor, their precise configurations can vary. For example, the positions of the sleeve on end 19 (and its corresponding parts on the pump heads 32, 34, 36) and the end 14 of the shaft, which interacts with it, can be reversed. In particular, the respective positions of the locking plates 22, the hooks 17 and the corresponding apertures 23 can be reversed. In this case, the locking plates 22 and the apertures 23 are placed on faces 13 of the mounting plates of the pump heads 32, 34, 36 and the hooks 17 are placed on the receiving plates. The configuration described and illustrated above is the most advantageous, in that it provides drive module 1 with a front face 18 free of fragile projecting elements, the breakage of which as a result of an impact would make drive module 1 unusable.

The foregoing description of exemplary embodiments of the invention have been presented for purposes of illustration and of description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of the invention. The embodiments were chosen and described in order to explain the principles of the invention and as practical applications of the invention to enable one skilled in the art to utilize the invention in various embodiments and with various modifications as suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents. 

1. A peristaltic pump comprising: a housing for a motor; a receiving plate mounted to the housing; a locking plate, the locking plate including a first aperture capable of receiving a hook extending from a pump head; a second aperture capable of receiving a drive shaft of the pump head; and a release member; and a biasing member elastically coupling the receiving plate with the locking plate; wherein use of the release member by a user causes movement of the locking plate relative to the receiving plate to release the hook when received in the first aperture thereby releasing the pump head from the locking plate.
 2. The peristaltic pump of claim 1, further comprising the motor.
 3. The peristaltic pump of claim 2, wherein the motor includes a motor drive shaft, and further wherein an end of the motor drive shaft is accessible through the second aperture.
 4. The peristaltic pump of claim 3, wherein the end of the motor drive shaft includes a sleeve and a spline extending from an inner surface of the sleeve.
 5. The peristaltic pump of claim 3, wherein the end of the motor drive shaft includes a central hub and a spline extending from an outer surface of the central hub.
 6. The peristaltic pump of claim 1, further comprising a drive module for controlling the motor.
 7. The peristaltic pump of claim 6, wherein the drive module comprises a control panel including a control for selecting an operating parameter of the pump head.
 8. The peristaltic pump of claim 1, further comprising the pump head, wherein the pump head comprises: a cassette configured to receive a tube; and a mounting plate mounted to the cassette, the mounting plate including the hook; and a third aperture wherein an end of the drive shaft is accessible through the third aperture.
 9. The peristaltic pump of claim 8, wherein the drive shaft of the pump head is operably coupleable with a motor drive shaft of the motor to control pumping of a fluid through the received tube.
 10. The peristaltic pump of claim 8, wherein the pump head further comprises: a second receiving plate mounted to the cassette; a second locking plate, the second locking plate including a fourth aperture capable of receiving a second hook extending from the second pump head; a fifth aperture capable of receiving a second drive shaft of the second pump head; and a second release member; and a second biasing member elastically coupling the second receiving plate with the second locking plate; wherein use of the second release member by the user causes movement of the second locking plate relative to the second receiving plate to release the second hook when received in the fourth aperture thereby releasing the second pump head from the second locking plate.
 11. The peristaltic pump of claim 10, wherein the second receiving plate mounts to the cassette on a side generally opposite the mounting plate.
 12. The peristaltic pump of claim 10, wherein the second drive shaft of the second pump head is operably coupleable with the drive shaft of the pump head to control pumping of a fluid through a second tube received by the second pump head.
 13. The peristaltic pump of claim 9, wherein the drive shaft of the pump head includes a central hub and a spline extending from an outer surface of the central hub; wherein the motor drive shaft of the motor includes a sleeve and a second spline extending from an inner surface of the sleeve; wherein the sleeve is capable of receiving the central hub; and further wherein the drive shaft operably couples with the motor drive shaft through an abutment of the spline with the second spline.
 14. The peristaltic pump of claim 9, wherein the drive shaft of the pump head includes a sleeve and a spline extending from an inner surface of the sleeve, wherein the motor drive shaft of the motor includes a central hub and a second spline extending from an outer surface of the central hub; wherein the sleeve is capable of receiving the central hub; and further wherein the drive shaft operably couples with the motor drive shaft through an abutment of the spline with the second spline.
 15. The peristaltic pump of claim 12, further comprising the second pump head, wherein the second pump head comprises: a second cassette configured to receive a second tube; and a second mounting plate mounted to the second cassette, the second mounting plate including the second hook; and a sixth aperture wherein an end of the second drive shaft is accessible through the sixth aperture.
 16. The peristaltic pump of claim 13, wherein an end of the spline is chamfered.
 17. The peristaltic pump of claim 2, wherein the motor includes a motor drive shaft, and further wherein an end of the motor drive shaft is accessible through the second aperture.
 18. The peristaltic pump of claim 1, wherein the release member is a push button.
 19. The peristaltic pump of claim 17, wherein the push button is mounted for movement in a first direction which causes compression of the biasing member.
 20. A peristaltic pump comprising: a housing for a motor; a receiving plate mounted to the housing; a locking plate, the locking plate including a hook; an aperture capable of receiving a drive shaft of a pump head; and a release member; and a biasing member elastically coupling the receiving plate with the locking plate; wherein use of the release member by a user causes movement of the locking plate relative to the receiving plate to release the hook from the pump head when the pump head is mounted to the locking plate. 